Home Security – Types of Walls and Hedging
Types of Walls
A concrete-section wall consists of a number ofslotted one on top of another between concrete posts. It provides a substantial barrier and plenty of privacy, and is cheaper to construct than a brick wall. Concrete walls require little or no maintenance, but they’re not very attractive and are rarely used in modern housing developments. They also attract graffiti, which can only be tackled by applying an anti-graffiti glaze before any vandalism can be carried out.
Made from pre-cast concrete blocks with moulded open patterns, screen walls are popular alternatives to solid structures. The blocks are stack bonded – set one on top of another so that the vertical mortar joints run continuously from the bottom of the wall to the top. They must be supported at each end by concrete pillar supports (pilasters) or brick piers. If the span of the wall is more than 3m (10 ft), intermediate supports will be required.
The disadvantage of this type of wall is that it provides a ready-made climbing frame for a burglar. However, defensive shrubs can be trained to grow against it. A screen wall allows the ground beyond the property to be observed easily.
A 2m (6 ft 6-in) brick wall capped with steep-sided coping stones will provide a reasonably secure boundary, but will be expensive to construct. Such a wall will require a substantial concrete foundation, but will need little maintenance for many years. To prevent rainwater from penetrating the top of the wall, the coping stones are normally bedded on a damp-proof membrane. The maximum safe height of a free standing 100-mm (4-in) thick brick wall without piers is only 300 mm (1 ft). Walls above this height need to be built with supporting piers at intervals of 1.8-2.4m (6-8 ft).
To stop people from sitting on a front garden wall, build it to the maximum height of 1m (3 ft) and top it with steep-sided coping stones or railings. Alternatively, grow a thorny plant against the wall in the front garden.
For hundreds of years, hedges of hawthorn, beech and other impenetrable thorny species have been used in the countryside to define and separate parcels of land, and contain livestock. In suburban gardens, hedges are grown primarily to define ownership, but also are an attractive security alternative to the fence, while providing additional privacy and a means of screening unsightly views, such as dustbins and sheds.
It is not uncommon for hedges in a back garden to be grown to a height of over 2m (6 ft 6 in). The higher the hedge, the greater protection it will provide, but bear in mind that it will also create more shade, and draw more water and nutrients from the soil. The ideal height for a front-garden hedge is around 1.2m (4 ft). This will allow your neighbours and passers-by to see any suspicious activity in front of your house, and permit you to monitor any activity around your neighbours’ homes from your windows.
When choosing hedging plants, do remember that prickly hedges cannot distinguish between friend and foe, and may fight back! Some varieties of hedging plant will grow quickly and require regular pruning.
A new hedge can take up to five or six years to establish itself as an effective barrier against intruders, but the reward is a natural boundary ‘wall’ full of berries and flowers, and foliage that changes colour with the seasons. If you want to plant a hedge, make sure that there is enough room for it in your garden, so that it does not spill into a neighbour’s property. If the hedge is to be planted on the boundary, talk to your neighbour first, as they may have a vested interest in sharing the cost. Remember, however, that a hedge is like a fence – if it’s too high, it may hide the burglar.